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1556 Chapter 16: Material Editor, Materials, and Maps
Left: Higher Max Distance value; Left: Lower Max Distance
value
Use AO as Detai l Enha ncement for GI /FG—Applies
short-distance AO, multiplying it with the
existing indirect illumination (Final Gathering or
GI/photons) to bring out small details.
The follow ing illustration depicts a model
helicopter that is lit almost exclusively by indirect
light:
Left: Without AO; Right: With AO
Note how the helicopter does not feel “grounded”
in the left image and the shadows under the
landing skids are far too vague. The right image
uses AO to “punch out” the details and the contact
shadows.
Shadow Color—Sets the darkness of the AO
shadows. It is used as the multiplier va lue for
completely occluded sur faces. In practice, a black
color ma kes the AO effect very dark; a middle-gray
color makes the effect less noticeable (brighter),
and s o on.
Custom/Global Ambient Light Color—Yo u c a n
specify a color for the ambient light used in AO, or
use the global color specified on the Environment
panel (page 3–272) > Common Parameters rollout.
This parameter is used for doing more traditional
AO; that is, supplying an imagined “ever-present
ambient lig ht” that is then attenuated by t he AO
effect to create shadows.
While traditional AO is generally used when
rendering without other indirect light, you can
also combine it with existing indirect light. Bear
in mind that this “ever-present ambient light” is
inherently non-physical, but can possibly help
lighten some troublesome dark corners.
Round Corners group
This effect rounds off corners and straight edges
as a rendering effect only; it has no effect on
geometry.
The rounding effect happens to convex corners
and surfaces that actually intersect. Concave
corners that merely touch will not display the
effect. To get the effect to work in concave corners
the objects must be pushed into each other a little.
The effect is intended for straig ht edges and is not
guaranteed to work properly for highly curved,
complex intersections.
Round Corners—When on, rounds off corners and
straight edges at render time.
Fillet Ra dius—Specifies the radius of the filleted
corners and/or edges.
Bl end wi th ot her mater i als —By default, the
rounding effect happens only between surfaces
of the same material, but if you turn this on the
filleting is performed against any material.
Inthefollowingimage,themoltenchocolateis
rounded off against the submerged objects even
though they use different materials. In actuality,
the molten chocolate is a completely flat plane.